What is the difference between IS 1785 Part 1 and Part 2?

Part 1 covers cold-drawn stress-relieved wire, while Part 2 covers wire in the 'as drawn' condition which has not undergone a stress-relieving thermal treatment.

What are the common sizes of 'as drawn' prestressing wire?

The standard nominal diameters are typically 3.0 mm, 4.0 mm, and 5.0 mm.

What is the maximum allowable sulphur and phosphorus content?

Both Sulphur and Phosphorus are limited to a maximum of 0.050 percent each.

IS 1785

: 2000

plain hard-drawn steel wire for prestressed concrete, Part 2: As the drawn wire

CurrentSpecializedSpecificationMaterials Science · Concrete Reinforcement (Steel)

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This standard covers the requirements for plain hard-drawn steel wire used for prestressed concrete in its 'as drawn' condition (without stress-relieving treatment). It specifies the chemical composition, physical tolerances, and mechanical tests such as tensile and reverse bend tests to ensure wire suitability for prestressing applications.

plain hard-drawn steel wire for prestressed concrete, Part 2: As the drawn wire

Quick Reference Values

Carbon content0.60 to 0.90 percent

Sulphur content (max)0.050 percent

Phosphorus content (max)0.050 percent

Standard nominal diameters3.0, 4.0, and 5.0 mm

Tolerance on nominal diameter± 0.05 mm

Practical Notes

Wire in the 'as drawn' condition has higher relaxation losses compared to stress-relieved wire (covered in Part 1). Use only where structural design explicitly accounts for higher relaxation.

A light film of rust is generally permissible and can improve bond, but the wire must be free from deep pitting, scales, or surface defects.